The bay bolete (Imleria badia, long known as Boletus badius) is one of the most widely gathered wild mushrooms of European woodland — a friendly, forgiving cousin of the great porcini that turns up in far larger numbers and asks far less of the forager. It takes its name from its cap: a smooth, softly domed dome the deep red-brown of a bay horse or a polished conker, faintly velvety and slightly tacky in the wet. Like all boletes it carries a spongy layer of fine tubes rather than gills beneath the cap, their pale cream-to-yellow pores opening as a soft mass that peels cleanly away. Its signature trick, and the surest way to know it, is that those pores flush a dull blue-green within seconds of a fingernail's touch — a harmless bruising reaction that never appears on a true cep. Milder, softer and less nutty than porcini but genuinely good, the bay bolete is the everyday wild mushroom of Central and Northern Europe: excellent sautéed, superb dried, and abundant enough that whole villages once put it up for winter.